Today many companies are offering decorative outdoor light emitting diode (LED retrofit kits and new LED fixtures in order to take advantage of the long life, excellent color and beam control and other benefits of LEDs. LEDs are temperature sensitive and generate a significant amount of heat, which must be removed from the fixture in order to assure long life and adequate illumination.
To date, most manufacturers have placed LEDs on heat sinks or printed circuit boards, which are either inside the optical and/or housing area or are mounted to an opaque metal top to provide heat extraction from the fixture. The problem with these designs is the high thermal resistance from LED heat source to the outside ambient air. Much of the heat remains trapped inside the optical cavity and lowers the life expectancy of the LED and limits the wattage of the LED light engine. Therefore, the life expectancy and total lumen package is less than is required for many applications. To date, no solution has been developed to provide for enhanced thermal performance with the light fixture having an external heat sink while incorporating several features to improve luminous light output or dispersion and directional control in many different application settings.
High power LED arrays are also very bright and it is both unappealing in many applications and, due to glare, poor for visibility where the individual LED array are visible as points of light. The use of LED arrays and a specially designed diffuser and the directional application of the LED arrays through an internal specially shaped reflector and various inserts minimizes glare and enhances aesthetic design and distribution of light.
A need exists for a new lighting fixture that employs features for improved heat dissipation and improved light distribution.